Spindle Cell Lesions of the Breast

Spindle cell lesions of the breast represent a heterogeneous group of reactive and neoplastic disorders that commonly present diagnostic challenges. Arguably, the most important of these lesions to recognize is spindle cell carcinoma, a type of metaplastic carcinoma. This review focuses on those spindle cell lesions of the breast that are most likely to be encountered in clinical practice or that produce particular diagnostic difficulties.